"Is there any information available how specific cannabis/hemp based products (e.g. tincture, etc.) could help in case of Tinitus? Thanks."
As far as reducing the annoying sensation of hearing sound when no external sound is present, cannabis will most likely have no appreciable effect.
"Together, these data suggest that while ACEA may be potentially otoprotective, selective CB1 agonists are not effective in diminishing the presence of tinnitus or hyperacusis."
However, cannabis can help with the irritablility, anxiety, insomnia and even the depression some tinnitus patients experience due to the difficulties of living with tinnitus. Also, most people with tinnitus find that their symptoms are worse when under stress, so relaxation techniques and low doses of cannabis should also help alleviate symptoms.
Despite laboratory findings in animal models of tinnitus that failed to demonstrate any benefit from activating isolated parts of the endocannabinoid system, many anecdotal reports of benefit from cannabis in human tinnitus can be found. Perhaps other biological activity happens when additional cannabinoids, terpenes, etc. are present, or perhaps the movement of attention away from the tinnitus stimulus that may result in humans from activating CB1 receptors is an explanation. I would encourage cautious experimentation with both CBD and THC dominant cannabis preparations. Remember that a tincture that is swallowed is an edible, and may require quite a while to produce any effects. Tinctures held in the mouth may be absorbed directly with effects usually within 10 minutes. Inhalation by smoking or vaporizing gives effects within a minute or two and makes it somewhat easier to adjust the amount being taken to match the effect being sought. I hope you find something of benefit for your symptoms.